Merrillite
Merrillite is a calcium phosphate mineral with the chemical formula Ca9NaMg7. It is an anhydrous, sodic member of the whitlockite group.Discovery and naming
The mineral is named after George P. Merrill of the Smithsonian Institution. Merrill had described the mineral from four meteorites in 1915: the Alfianello, Dhurmsala, Pultusk, and Rich Mountain meteorites. The mineral was not recognized as distinct from whitlockite, however, by the IMA until 1975.Occurrence
Merrillite is a very important constituent of extraterrestrial rocks. It occurs in pallasites, lunar rocks, martian meteorites, and many other meteorite groups.
